U.S. Pat. Nos. 3,262,872, W. A. Rhodes et al, and 3,346,470, R. W. Henes, describe apparatus which produces hydrogen and oxygen electrolytically from water. The gases produced are employed directly as fuels for welding and cutting torches incorporated as a part of the same apparatus.
The electrical current for the electrolysis process is supplied through a step-down transformer and rectifier and its control is accomplished by means of a solid state phase-control circuit located ahead of the step-down transformer. Because the transformer constitutes an inductive load on the phase-control circuit, however, the conventional phase-control circuit is not as effective as desirable in providing smooth continuous control over the full range of current required for the process.
The present invention addresses this problem and discloses improved electronic control circuits which provide the smooth continuous control and other features desired for this and similar applications.